How much sleep you really need depends on your menstrual cycle

The week before I get my period, everything feels harder: exercise is like wading through concrete; everyone annoys me, often simply by opening their mouths; and I am suddenly ravenous.

A girlfriend once told me she could almost 'feel the hate drain from her body' (if you'll excuse the graphic metaphor) when her period finally came. It made me laugh, because I couldrelate. Oh boy, could I relate.

Sure, herein lies another short straw of womanhood - but what can you do? Usually, I tend to bunker down, armed with a few blocks of Cadbury, and weather the storm. I've always blamed hormones for this mental and physical rollercoaster and, until recently, it had never occured to me that women should be getting more sleep before our periods. But according to sleep expert Dr Carmel Harrington, in addition to the 10 tonnes of caramello, often this is what our body is crying out for.

"This is not well-known but I think it should be,” Dr Harrington tells me, down the phone. Young fertile women need an extra half an hour, minimum, in the second half of our cycles, due to the increase in progesterone, which leaves us sleepy, she says.

The problem of course being that for most women - many of whom, like me, are falling short as it is - sneaking in an extra half an hour is a fantasy, up there with daily yoga and celery juice.

Dr Harrington gets it, she really does, but the problem is, she says, that we are paying for this "sleep debt" as a result. "Normally in this day and age, where women have 9-5 jobs, you can't sleep in extra and so you ignore that feeling and as it goes on through the second half of your cycle, towards the last 10 or 12 days, you're actually very sleep deprived... if you're not responding to that tiredness, you start to get all the characteristics of being sleep deprived: you're cranky, you're moody, you can be a little bit emotional, all those characteristics are now being treated as PMS."

I recently tracked my sleep using new A.H. Beard sleep technology, which showed I feel asleep in three minutes and slept for nine hours (it was the weekend). A slumber even I was surprised by, given I'm usually scraping the barrel with six - maybe seven, if I’m lucky - hours a night. But Dr Harrington says this is clear evidence of my own "sleep debt". She says women my age, in their late 20s, should be aiming for eight hours of sleep a night, and an extra half hour on top of that in the second half of our cycles. Meaning by Dr Harrington's calculations, most days I am falling shamefully short.

The answer, while not particularly groundbreaking or sexy, is to go to bed earlier, Dr Carrington says, promising "because you are tireder you will be able to go to sleep". The only problem being that most of us have a "peak of alertness" at around 9pm, which means if we try to go to sleep then (or earlier) we often end up tossing and turning. "One of the ways we can affect that peak is to reset your biological clock. So if you wake up at 8am around about 16 hours later you'll be ready to go to sleep. So the most important thing we can do is to wake up at the same time every day."

Image: Getty.Source:BodyAndSoul

Avoid sleep stealers

To get better sleep, we also need to be aware of our "sleep stealers" and tread with caution accordingly, she warns. Perhaps unsurprisingly, the main culprits come in the form of many of life's great pleasures: booze, sugar, and caffeine.

"Alcohol is a sleep stealer," Dr Carrington says emphatically. "It's toxic to the body so the works hard to get rid of it - you might be able to get to sleep OK but about five hours later you'll wake up and have pretty disrupted sleep." Dr Carrington adds that people don't often tie alcohol with poor sleep because the disruption to sleep occurs "so many hours later". As for caffeine, she recommends cutting yourself off after midday - and espresso martinis are a just a "disaster" waiting to happen ("I am amazed how popular they are").

However, she caveats, these things have different effects on different people, so your best bet is to be aware of your sleep stealers and manage accordingly.

Why sleep matters

For some reason, sleep tends to be the pillar of health most forgotten by our celery juice drinking, yoga-doing, wellness-obsessed society. Dr Carrington thinks so too.

"People actually need to understand that there are three pillars of health," she reasons. "We are very well-schooled in exercise and what we need to do there. We're very well schooled what we need to do in nutrition - even if we don't do the right things all the time, we know that we are not doing the right things - but nobody understands about sleep. They think because we are in a 24/7 world and we can be shopping at 3am in the morning and having fun that this is perfectly reasonable and we'll catch up another time. Well, we actually don't catch up."

And while most of us know we should be getting more sleep, few of us fully grasp the havoc a sleep deficit is wreaking on our health. And if we did, we might be starting to wonder whether getting to that 5am HIIT class - on five or six hours sleep - is worth it. "Nutrition has become a very commercialised entity and same as exercise and because of that people are bombarded and spend an awful lot of time exercising, which is great but we mistake that how much we exercise affects our weight - research shows 80% to 90% of our weight is what we eat not how much we exercise."

Dr Carrington drills down on the fact there is a lot of research to show poor sleep leads to increased weight, with our bodies likely to drop our metabolic rate by 5 to 10 per cent to conserve energy. Add to this the fact this is also when most of us reach for coffee and carbs to summon energy, and you've got a surefire recipe for weight gain.

Aside from the long-term health effects, like hypertension, obesity, and so on, in the short-term, people who skimp on sleep are more likely to suffer depression or an altered mood state.

Dr Harrington's best sleep tips

Get up earlier

You need to condition your body by getting up earlier (and going to bed earlier) on a regular basis. Generally, we will start to feel tired about 16-hours after we get up.

Skip the post-lunch caffeine

Avoid coffee coffee after midday, as well as other substances - “sleep stealers” - which are likely to interfere with a good night’s rest.

Make sleep a priority

"Basically I say you have 8 hours of work, 8 hours of sleep and 8 hours of other. If you decided to work more - which we often do - we so often take from 8 hours of sleep but those 8 hours of sleep should be non-negotiable, it just means you can’t go to the gym that day."

Switch off an hour before bed

Switch off ALL technology, have a shower, dim lights, maybe do a relaxation exercise - read a novel. A real novel and you’ll find that process you’ll become conditioned to. Parents are not giving their children a good bedtime routine.